Shift of Earth’s Magnetic North Pole ...

[Peter Lemkin]

I decided to to conduct a Doh! check just to see if the foregoing essays were accurate. The easiest way was to take a compass reading. Being a boy scout type, I have a Silva compass, which is one of the best available.

Magnetic north is still magnetic north. Maybe a degree or two off where I am used to seeing it, but nothing more than that.

So, is this an April 1st story, or am I short of something on the scientific brawn front?

From Wikipeadia, but correct: Change of declination in time and space

Magnetic declination varies both from place to place, and with the passage of time. As a traveller cruises the east coast of the United States, for example, the declination varies from 20 degrees west (in Maine) to zero (in Florida), to 10 degrees east (in Texas), meaning a compass adjusted at the beginning of the journey would have a true north error of over 30 degrees if not adjusted for the changing declination.

In most areas, the spatial variation reflects the irregularities of the flows deep in the earth; in some areas, deposits of iron ore or magnetite in the Earth's crust may contribute strongly to the declination. Similarly, secular changes to these flows result in slow changes to the field strength and direction at the same point on the Earth.

The magnetic declination in a given area that may (most likley will) change slowly over time, possibly as little as 2-2.5 degrees every hundred years or so, depending upon how far from the magnetic poles it is. For a location closer to the pole like Ivujivik, the declination may change by 1 degree every 3 years. This may be insignificant to most travellers, but can be important if using magnetic bearings from old charts or metes (directions) in old deeds for locating places with any precision.

Simply speaking, true north is the direction in which the north pole is located along the Earth's rotational axis, while magnetic north is the direction toward which the compass needle points.
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Its subtle old boy...it takes time to change, like good whiskey.....so have another. Pour me one, better yet, make mine a double - no ice.

If you were to put that map on a globe or world map with correct 'projection' you would see that from when you purchased your trusty 'ol compass to now the number of degrees change is minor, a degree or two [guessing]. If you have a good Silva, Suuntu or other compass, you can even correct it@!

Oh, by the way the door mat sales are ppppffffft! You took the best part of that partnership by caveat!